class Solution:
    def reverseString(self, s):
        """
        Do not return anything, modify s in-place instead.
        """
        # 双指针
        left = 0
        right = len(s) - 1
        while left < right:
            tmp = s[right]
            s[right] = s[left]
            s[left] = tmp
            left += 1
            right -= 1
        return s


if __name__ == '__main__':
    s = Solution()
    print(s.reverseString(["h","e","l","l","o"]))



